In the world of project management, a "program" (sometimes spelled as "programme" in the UK) is a set of projects that share a common program-level objective.
A bank may need to comply with new regulations that affect multiple departments and business units. It may set up a project to revised technology platforms, a project to review the obligations and document what the bank has to do, a project to upgrade business processes to meet the regulations, a project to develop and deliver training to staff. And finally, a program that oversees and integrates the work of all these projects.
There is clear boundary between projects and programs on the one hand, and operations on the other hand. The project and program team delivers the requested change. The operations team (also known as business-as-usual teams) operate the business under the new change. Hopefully what is delivered by the project and program team eables the operations team to meet the regulations.
In this world, there is a clear delineation of responsibilities. The project and program team are only responsible for delivering what it was asked of. They are not responsible for compliance with regulations. The operations team is not responsible for what is to be delivered. (In many cases, there are temporary workers who will move on to other projects at other companies). They are just the recipients. But they are responsible and accountable for meeting the regulations.
It is obvious that this arrangement leaves the door open to problems. In practice, the operations team work closely with the project and program teams to ensure that what is delivered is what the operations team needs.
There is another discipline that uses the word 'program'. In Program Evaluation, a program refers to the operation of the new world. Its purpose is to evaluate whether and how well the new operation is being executed an how well it is delivering on the benefits that were the basis for why the program was undertaken.
Schools are heavy users of program evaluations. They implement (or are forced to implement) a program to improve the reading abilities of their primary school students. Program evaluation assesses the ongoing success of the program and as appropriate recommends adjustments.